Revival !

I'm glad to announce that the website hosted under the name "" since 1999, which I had to shutdown a few years ago, will slowly come back to life here.

The structure of the website will be simple : each equipment will have its own blog entry, pages will be used for categories.

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Paris, France, May 2014.

Wednesday, April 17, 2013

ML 3 | 2 x 200W amplifier | 1979 - 1987

The ML-3 is a hell of a beast ! With its weight of 52 Kg (116lbs) and its depth of 62cm (20½") the only place where it can fit is... the ground. Hopefully, working in class AB, it doesn't need that much electricity most of the time. The only question is, what kind of loudspeakers may need this POWER amplifier?

This amplifier is made of exactly 2 mono amplifiers, each on each side, with the two big (1,2 KVA) toroidal transformers put in the middle of the chassis next to some 36,000µF capacitors (100V). It can output 45 Volts at 30 Amperes: you'd better use fat speakers cable cables.

Pro and Cons

Pro Cons
Stereo, high power. Large and heavy. 
Can drive any speaker. Lots (20) output transistors which can be expensive to replace.
An engineer delight :-) Specific (non standard) connectors used.


Power Output: 200 Watts per channel into 8 Ohms, 20 Hz - 20 Khz, < 0.2% THD.
Input Sensitivity: 1 Volt RMS for 200 Watts into 8 Ohms.
Input Impedance : 20 K Ohm shunted by 250 pf.
Max Power Consumption: 2 Ohm load, both channels just below clipping, 2.5 kW, 200 W at idle.
Weight: 52 Kg (~120 lbs).
Dimensions:   483mm (19")  266mm (10½")  620mm (20½")


ML-3 Stereophonic Power Amplifier [download]
ML-2 class A/B power amplifier [download]


La Nouvelle Revue du Son [download]

Technical information

Warning and cabling [download]



  1. Can this Amplifier drive any speaker??

  2. Absolutly any loudpseaker of any type, including magnepan or electrostatic panels.

  3. I hava an ML-3 that I use with a Threshold NS-10 Preamp. Is that an ok match??

  4. Check the max output level of the preamp (in Volts, from the epcs) and see if it matches the ML3 max input.. But you can always try it without any risk if you start at LOW volume.

  5. No. It can't drive the Apogee Scintilla or The Apogee (Fullrange) directly without the Apogee transformer as the ML-2 can.

  6. If I have one of these power amps laying around, I will want to use it to power (variable frequency) Electric tools such as my impact power drill etc.